RESUMO
BACKGROUND: The utilization pattern of dronedarone was unknown, especially regarding prescribers' compliance with the product's prescribing information (PI) following its availability and the implementation of the Food and Drug Administration-approved risk evaluation and mitigation strategy for the drug in the United States. OBJECTIVE: This study was designed to evaluate the dronedarone prescribers' adherence to PI regarding the following contraindications: (1) patients with heart failure (HF) with a recent decompensation requiring hospitalization or referral to a specialist, (2) concomitant use of potent CYP3A4 inhibitors, and (3) concomitant use of QT-prolonging drugs. METHODS: Patients prescribed dronedarone between July 2009 and August 2010 were identified through LabRx. The following rates surrounding dronedarone use were examined: (1) atrial fibrillation or atrial flutter in the past year, (2) worsening or hospitalization for HF within the month before prescription, and (3) concomitant prescription of potent CYP3A4 inhibitors and concomitant prescription of QT-prolonging drugs within the following month. RESULTS: A total of 4595 dronedarone prescriptions were filled by 1820 patients. More than 94% of the participants had ≥1 diagnosis of atrial fibrillation or atrial flutter in the previous year. Worsening of or hospitalization for HF was found in 61 (3.4%) patients within the month before receiving dronedarone, including 18 patients with HF as the primary cause for hospitalization. Potent CYP3A4 inhibitors were prescribed to 10 (0.6%) patients within a month following dronedarone initiation, 6 of whom received them for topical use only. QT-prolonging drugs were prescribed to 67 (3.7%) patients within a month following dronedarone initiation, among which >90% were other antiarrhythmics. CONCLUSIONS: Dronedarone was used mostly in compliance with PI and risk evaluation and mitigation strategy in the studied population. In the LabRx database, dronedarone was commonly dispensed to patients with cardiovascular risk factors and rarely dispensed to patients with contraindications such as worsening HF or hospitalization for HF or with concomitant prescriptions of potent CYP3A4 inhibitors, QT-prolonging drugs, or both.
